atcoder#ARC068B. [ABC053D] Card Eater

[ABC053D] Card Eater

Score : 400400 points

Problem Statement

Snuke has decided to play a game using cards. He has a deck consisting of NN cards. On the ii-th card from the top, an integer AiA_i is written.

He will perform the operation described below zero or more times, so that the values written on the remaining cards will be pairwise distinct. Find the maximum possible number of remaining cards. Here, NN is odd, which guarantees that at least one card can be kept.

Operation: Take out three arbitrary cards from the deck. Among those three cards, eat two: one with the largest value, and another with the smallest value. Then, return the remaining one card to the deck.

Constraints

  • 3N1053 \leq N \leq 10^{5}
  • NN is odd.
  • 1Ai1051 \leq A_i \leq 10^{5}
  • AiA_i is an integer.

Input

The input is given from Standard Input in the following format:

NN

A1A_1 A2A_2 A3A_3 ... ANA_{N}

Output

Print the answer.

5
1 2 1 3 7
3

One optimal solution is to perform the operation once, taking out two cards with 11 and one card with 22. One card with 11 and another with 22 will be eaten, and the remaining card with 11 will be returned to deck. Then, the values written on the remaining cards in the deck will be pairwise distinct: 11, 33 and 77.

15
1 3 5 2 1 3 2 8 8 6 2 6 11 1 1
7